No, you're not seeing double. This is all material that used to appear in a node called jumping just before the elevator hits the ground, which was deleted. So here is its substance, again.

There's really no point in doing it. Not because of little things like terminal velocity and air resistance (you're not going to fall for long enough to get anywhere near terminal velocity), but because of Big Things. Things like Physics and conservation of energy. One way to see this is to set up some equations and solve them. But if you want to verify this without all that nasty mucking about with forces and the need actually to understand Physics, you can cheat.

Suppose you're in a lift (as they're called in English) at some height, and you start freefalling along with the lift. Eventually, no matter what faces you pull at the security camera behind the mirror, lightbulbs you shatter, or jumps you perform, you will smash into the floor (the lift will also do so). In your case, you will have converted your potential energy (from being at that height initially) into kinetic energy (at height 0, when you crash into non-tomato ketchup). So it's always the same kinetic energy, and always the same velocity that you crash with.

OK?